Part of a larger Program Project application dealing with fundamental and applied neuroendocrinoloy in the field of reproduction, growth, other pituitary functions and diabetes. Specifically, it is proposed to synthesize and assay for biological activity analogs of somatostatin with tailored activities on secretion of growth hormone, glucagon, insulin and to make these available for clinical studies in juvenile diabetes. To study the physiology of secretions of somatostatin after having developed a specific radioimmunoassay for somatostatin. To continue current research on the conformation of TRF and obtain anti-TRF analogs. To isolate and characterize hypophysiotropic corticotropin releasing factor. To investigate mechanism of action of hypothalamic hypophysiotropic peptides at the cellular level in pituitary, pancreas and brain tissues. Recent observations on the newly developed technical capability to produce insulin of greater purity than even achieved previously will be expanded particularly to assess the relative biological activities of the "superclean insulin" and the non-insulin components of currently available "insulin preparations". The roles of the various endorphins on neuroendocrine functions and other physiological and behavioral functions of the brain will be further investigated.